1. Field of this Invention
This invention relates to a process for the production of succinylosuccinic acid diester from .gamma.-haloacetoacetic ester in a water medium by means of at least one strong base.
2. Prior Art
Succinylosuccinic acid diester has been produced by reaction from .gamma.-chloroacetoacetic ester in water by reaction with sodium phenolate; in that case, a yield of only 58 percent was obtained (Bull. Soc. Chim. France 29, 192, pp. 402-6).
Succinylosuccinic acid diester has been produced from succinic acid diethyl ester (as a starting material). In that case the succinic acid diethyl ester was reacted with sodium ethylate. The highest yield that was achieved by that process was around 80 percent (U.S. Pat. No. 3,024,268). The main disadvantage of that process, however, is that the isolation of the resultant succinylosuccinic acid diester is exceedingly cumbersome, difficult and time cousuming. Furthermore, large quantities of solvent are needed in that process.
Succinylosuccinic ester have been prepared from ethyl succinate and Na using a double Claisen reaction. Whitmore, F. C., "Organic Chemistry", 2nd Ed. (1951), p. 381. Succinylosuccinic esters have been produced by reacting NaOC.sub.2 H.sub.5 and ethyl succinate. Whitmore, ibid, p. 708.
See also U.S. Pat. No. 3,803,209.